HMS E30 was a British E-class submarine built by Armstrong Whitworth, Newcastle upon Tyne.

British E-class submarines had fuel capacities of 50 long tons (51 t) of diesel and ranges of 3,255 miles (5,238 km; 2,829 nmi) when travelling at 10 knots (19 km/h; 12 mph).

She put a prize crew aboard Kong Inge and ordered the merchant ship to Leith for examination.

E30's patrol was cut short when she suffered a battery explosion on the morning of 7 April, killing four men and forcing her return to base.

[8] On 15 May 1916, E30 set out for a patrol in the Kattegat, and on 18 June she encountered the German steamer Trave, whose crew abandoned ship after E30 fired a warning shot.

Norway raised a protest about the attempt to stop Prunelle, claiming it took place in territorial waters.